Neisseria and Streptococci Reference, Department of Bacteriology, Mycology and Parasitology, Division of Microbiology and Diagnostics, Statens Serum Institut, Artillerivej 5, 2300, Copenhagen S, Denmark, LLM@SSI.dk.
The aim of this study was to characterise the group B streptococci (GBS) isolates causing severe invasive infections in patients >15 years of age in Denmark from 1999 to 2004. A total of 411 invasive GBS isolates were phenotypically characterised by the capsular polysaccharide (CPS) serotype and protein Calpha, Cbeta and R4. The incidence of invasive GBS disease ranged from 2.2 to 3.2 per 100,000 adults in the study period, being highest among adults over 65 years of age. Diabetes was observed in 15% of the cases, 12% had alcohol abuse and 7% had cancer. Of all isolates, 77% were CPS serotypes Ia, Ib, III or V. The surface proteins Calpha or R4 were detected as the only protein in 57% of the GBS isolates. Cbeta was detected in 12% of the isolates, but always in combination with either Calpha or both Calpha and R4. The incidence of invasive GBS infections continued to increase in Denmark from 1999 to 2004. In that period, the overall case fatality was 14%. The most prevalent CPS serotypes were serotypes III, Ia, V and Ib. The most prevalent surface protein was R4 when testing for R4, Calpha and Cbeta. There was no clear relation between the GBS phenotype and infections with fatal outcome.
To identify determinants for mortality and sequelae and to analyse the spatial distribution of meningococcal disease, we linked four national Danish registries. In the period 1974-2007, 5924 cases of meningococcal disease were registered. Our analysis confirms known risk factors for a fatal meningococcal disease outcome, i.e. septicaemia and high age (>50 years). The overall case-fatality rate was 7.6%; two phenotypes were found to be associated with increased risk of death; C:2a:P1.2,5 and B:15:P1.7,16. B:15:P1.7,16 was also associated with excess risk of perceptive hearing loss. The incidence rates of meningococcal disease were comparable between densely and less densely populated areas, but patients living further from a hospital were at significantly higher risk of dying from the infection. To improve control of meningococcal disease, it is important to understand the epidemiology and pathogenicity of virulent 'successful clones', such as C:2a:P1.2,5 and B:15:P1.7,16, and, eventually, to develop vaccines against serogroup B.
We report a large foodborne outbreak due to group A streptococci (GAS), which caused acute tonsillo-pharyngitis in 200-250 patrons of a company canteen in Copenhagen, Denmark, in June 2006. A retrospective cohort study of canteen users showed that consumption of cold pasta was associated with an increased risk of illness (attack rate 68%, risk ratio 4.1, P